Add functions to create media links between source and sink subdevices,
based on the fwnode endpoint connections between them:
v4l2_create_fwnode_links_to_pad() - create links from a source subdev to
a single sink pad based on fwnode
endpoint connections.
v4l2_create_fwnode_links() - create all links from a source to sink subdev
based on fwnode endpoint connections.
These functions can be used in a sink's v4l2-async notifier subdev
bound callback to make the links from the bound subdev.
Signed-off-by: Steve Longerbeam <slongerbeam@xxxxxxxxx>
---
drivers/media/v4l2-core/v4l2-mc.c | 95 +++++++++++++++++++++++++++++++
include/media/v4l2-mc.h | 48 ++++++++++++++++
2 files changed, 143 insertions(+)
diff --git a/drivers/media/v4l2-core/v4l2-mc.c b/drivers/media/v4l2-core/v4l2-mc.c
index 0fffdd3ce6a4..ba2f2b8dcc8c 100644
--- a/drivers/media/v4l2-core/v4l2-mc.c
+++ b/drivers/media/v4l2-core/v4l2-mc.c
@@ -309,6 +309,101 @@ int v4l_vb2q_enable_media_source(struct vb2_queue *q)
}
EXPORT_SYMBOL_GPL(v4l_vb2q_enable_media_source);
+int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,
+ struct media_pad *sink)
+{
+ struct fwnode_handle *endpoint;
+ struct v4l2_subdev *sink_sd;
+
+ if (!(sink->flags & MEDIA_PAD_FL_SINK) ||
+ !is_media_entity_v4l2_subdev(sink->entity))
+ return -EINVAL;
+
+ sink_sd = media_entity_to_v4l2_subdev(sink->entity);
+
+ fwnode_graph_for_each_endpoint(dev_fwnode(src_sd->dev), endpoint) {
+ struct fwnode_handle *remote_ep;
+ int src_idx, sink_idx, ret;
+ struct media_pad *src;
+
+ src_idx = media_entity_get_fwnode_pad(&src_sd->entity,
+ endpoint,
+ MEDIA_PAD_FL_SOURCE);
+ if (src_idx < 0)
+ continue;
+
+ remote_ep = fwnode_graph_get_remote_endpoint(endpoint);
+ if (!remote_ep)
+ continue;
+
+ /*
+ * ask the sink to verify it owns the remote endpoint,
+ * and translate to a sink pad.
+ */
+ sink_idx = media_entity_get_fwnode_pad(&sink_sd->entity,
+ remote_ep,
+ MEDIA_PAD_FL_SINK);
+ fwnode_handle_put(remote_ep);
+
+ if (sink_idx < 0 || sink_idx != sink->index)
+ continue;
+
+ /*
+ * the source endpoint corresponds to one of its source pads,
+ * the source endpoint connects to an endpoint at the sink
+ * entity, and the sink endpoint corresponds to the sink
+ * pad requested, so we have found an endpoint connection
+ * that works, create the media link for it.
+ */
+
+ src = &src_sd->entity.pads[src_idx];
+
+ /* skip if link already exists */
+ if (media_entity_find_link(src, sink))
+ continue;
+
+ dev_dbg(sink_sd->dev, "creating link %s:%d -> %s:%d\n",
+ src_sd->entity.name, src_idx,
+ sink_sd->entity.name, sink_idx);
+
+ ret = media_create_pad_link(&src_sd->entity, src_idx,
+ &sink_sd->entity, sink_idx, 0);
+ if (ret) {
+ dev_err(sink_sd->dev,
+ "link %s:%d -> %s:%d failed with %d\n",
+ src_sd->entity.name, src_idx,
+ sink_sd->entity.name, sink_idx, ret);
+
+ fwnode_handle_put(endpoint);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(v4l2_create_fwnode_links_to_pad);
+
+int v4l2_create_fwnode_links(struct v4l2_subdev *src_sd,
+ struct v4l2_subdev *sink_sd)
+{
+ unsigned int i;
+
+ for (i = 0; i < sink_sd->entity.num_pads; i++) {
+ struct media_pad *pad = &sink_sd->entity.pads[i];
+ int ret;
+
+ if (!(pad->flags & MEDIA_PAD_FL_SINK))
+ continue;
+
+ ret = v4l2_create_fwnode_links_to_pad(src_sd, pad);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(v4l2_create_fwnode_links);
+
/* -----------------------------------------------------------------------------
* Pipeline power management
*
diff --git a/include/media/v4l2-mc.h b/include/media/v4l2-mc.h
index 5e73eb8e28f6..302674d2a619 100644
--- a/include/media/v4l2-mc.h
+++ b/include/media/v4l2-mc.h
@@ -12,6 +12,7 @@
#include <media/media-device.h>
#include <media/v4l2-dev.h>
+#include <media/v4l2-subdev.h>
#include <linux/types.h>
/* We don't need to include pci.h or usb.h here */
@@ -84,6 +85,53 @@ void v4l_disable_media_source(struct video_device *vdev);
*/
int v4l_vb2q_enable_media_source(struct vb2_queue *q);
+/**
+ * v4l2_create_fwnode_links_to_pad - Create fwnode-based links from a
+ * source subdev to a sink subdev pad.
+ *
+ * @src_sd - pointer to a source subdev
+ * @sink - pointer to a subdev sink pad
+ *
+ * This function searches for fwnode endpoint connections from a source
+ * subdevice to a single sink pad, and if suitable connections are found,
+ * translates them into media links to that pad. The function can be
+ * called by the sink subdevice, in its v4l2-async notifier subdev bound
+ * callback, to create links from a bound source subdevice.
+ *
+ * .. note::
+ *
+ * Any sink that calls this function must implement the .get_fwnode_pad
+ * media operation in order to verify endpoints passed to it are owned
+ * by it.
+ *
+ * Return 0 on success or a negative error code on failure.
+ */
+int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,
+ struct media_pad *sink);
+
+/**
+ * v4l2_create_fwnode_links - Create fwnode-based links from a source
+ * subdev to a sink subdev.
+ *
+ * @src_sd - pointer to a source subdevice
+ * @sink_sd - pointer to a sink subdevice
+ *
+ * This function searches for any and all fwnode endpoint connections
+ * between source and sink subdevices, and translates them into media
+ * links. The function can be called by the sink subdevice, in its
+ * v4l2-async notifier subdev bound callback, to create all links from
+ * a bound source subdevice.
+ *
+ * .. note::
+ *
+ * Any sink that calls this function must implement the .get_fwnode_pad
+ * media operation in order to verify endpoints passed to it are owned
+ * by it.
+ *
+ * Return 0 on success or a negative error code on failure.
+ */
+int v4l2_create_fwnode_links(struct v4l2_subdev *src_sd,
+ struct v4l2_subdev *sink_sd);
/**
* v4l2_pipeline_pm_get - Increase the use count of a pipeline
--
2.17.1
